Pen



FIG. 1 is a bottom view of a pen, showing my new design.

FIG. 2 is a front view thereof.

FIG. 3 is a left view thereof.

FIG. 4 is a rear view thereof.

FIG. 5 is a right view thereof; and,

FIG. 6 is a top view thereof. 

CLAIM The ornamental design for a pen, as shown and described. 